Red tetrazo dye.



* "enrrsn semi m MEYER, OF ELBEBFELD, GERMANY, ASSIGNOR TO FARBENEABRIKEN VORM. FRIEDR BAYER & 00., OF ELBERFELD, GERMANY, A CORPORATION OF GERMANY.

RED I TETELAZO DYE.

No. assess.

To all whom it may concern: Be it known that l, EMIL MEYER, chemist, citizen of the Germen Empire, residing at l Elberfeld, Germany, Kingdom of Prussia, have invented new and useful Improvements in Red Tetrazo'Dyes, of which the following IS a specification.

: anew tetrazo-dyestuii which 18 o 1i acid with a red color.

weightz' 2-53v are diazotize I sary "quantity of hydrochloric acid; the reinto a well cooled' solution containing 608 My invention relates to the pre aration of lit'ained by combining one molecule of the tetrezo-compoundof meta-dichlorobenzidin having the formula.

with two molecules of 2-nephthol-3fi-disulionic acid. lhe new dye is after being dried and pulverized in the shape of its sodium salt a dark powder soluble in water with a red color andsoluble in concentrated sulfuric Upon reduction with stannous chlorid and hydrodhloric acid nietadichlorobenzidin and bitmino-Zmephthol- Sfi-disultonio acid are obtained. lt dyes WOOl red shades remarkable for :fastness to light and to milling.

In carrying out my invention practically. I can procee as follows, the parts being by arts of meta-dichlorobenzidin in the usual manner by means of 13.8 parts of sodiuni nitrite and the necess ecinc'stmn of Letters Patent. Application filed February 1, 1903. Serial No. $13,903.

suiting tetrazo-compound is thenintroduced Patented. May 26, 1908.

parts of 2 nabhthol-3.6-disulfonic acid and an excess of sodium carbonate. 'The formation of the dye is complete after a short time.

The dyestufi is preclpitated by the addition of coinmon salt, filtered off and dried.

Having now described my invention and in what manner the same is to be performed,

what I claim as new and desire to secure by Letters Patent is The herein described new tetrazodyes'tufl obtainable by combining the tetrazo-comound of meta-dichlorobenzidin having the formula:

with two molecules 'of 2:naphthol-3.6 disulionic acid, which (1 e'stufl is after being driedand pulverized int e shape of itssodium salt.

a dark powder soluble in water. with a red' color and soluble in concentrated sulfuric acid with a red color; yielding upon reduction 1 with stannous"chlorid and .hydrochloric acid meta-dichlorobenzidin and 1- amino-2-na dyeing woo from scidbathsred shades, substantially as hereinbefore described. I

In testimony whereof I. have hereunto set my hand in .the presence of two subscribing witnesses.

3 EMIL MEYER. Witnesses: I I

O'r'ro Komo, v I WM. WASHINGTON BRUNSWICK.

hthol-fifi-disulforii acid; and 

